Bill Thanks for your comments. You asked me why does it matter that the board has no crown or even counter crown after removal from the case. In a situation like this the board is being forced to crown by the bevel of the inner rim. The soundboards surface is stretched or in other words the board is in tension in this situation. The whole idea with crown is to make it possible for downbearing to compress the soundboard panel. Compressing the board with d.b. has a number of beneficial effects because doing so increases the speed that vibrations travel in the board. The effects include improved sustain in the treble, more efficient soundboard function that can increase the volume of sound, clearer and rounder tone and the overall widening of the dynamic range. More on this subject will be found in my upcoming article in PTJ on the relationship between downbearing and piano tone. This should be coming out in August or September. Besides the fact that having the board in tension may adversely effect the tone it will also effect the durability. Wood is particularly week in tension across the grain. When there is minimum crown in a soundboard the downbearing compresses only the area nearest the bridge. Further away the surface is in tension. New soundboards with adequate crown will distribute the d.b. load evenly throughout the boards surface. This arrangement is more durable. It is worth wile to examine the difference in crown between a new and old board outside of their cases. A new well made board will have as much as 5/8 crown at 8% EMC. This is what the old board had originally! I would like to comment briefly on the other issue you raised; the validity of soundboard replacement. I have certainly experienced the same things that you have in restringing older pianos without replacing the board. The results I got where impressive to most of my client. I know that I made enormous improvements to the piano and the jobs were a value to my clients. I also gained a great deal of valuable experience. A number of things though could be said to dampen my enthusiasm. The pianos that I rebuilt in this way were long over due for attention. Just about any worthwhile efforts on my part would have made a marked improvements. Another aspect is that sooner or latter many of these instruments developed problems. Ribs reglued so carefully came unglued again and the hours I spent shimming the cracks became wasted effort as I witnessed the progress of pairs of cracks where one was before. These sorts of problems made me realize that I would have to change my attitude and approach if I was to be happy and prosper in my work. I learned that it just wasnt worth the frustration and risk to save the board. What attitudes did I harbor that blocked me from seeing this earlier? The taboo is one; technicians are not supposed to tinker with the heart and soul of the piano and soundboards are too mysterious to understand. All I can say to this is that piano technicians designed and built piano soundboards and we today can develop the knowledge and skills to work on any and all aspects of the piano. The durability issue; the soundboard will last for ever, after all, Strads just keep sounding better and better. Knowing what I know now about wood technology and my experience with rebuilding, I recognize the inevitable; soudboards are not a permanent element of the piano. Because of the factors of compression set and time dependent deformation, soundboards that have crown and downbearing will certainly deteriorate over time and eventually fail to function as they were intended. We should remember that the violin functions differently than the piano and that a violin with a flat top plate would still work but sound pretty bad. The issue of tone quality; a new board will not sound any better than the old one. In one regard I can agree with this, many shops are installing inferior boards. I have witnessed here on the east cost large operations that make no attempt to crown their boards. A new flat board will not sound any better than an old flat board. The bottom line on the quality of tone issue is personal experience and taste, both of which vary a great deal from tech. to tech. After experiencing the improved tone quality in the middle of the scale and in the lower treble as well as the expanded dynamic rang I now find it hard to imagine going back to using older boards in my rebuilding. Voicing now is a pleasure, seeing haw far I can push the dynamic range without distortion. The results of this are not always apparent to my clients but when an experienced player has this at their touch they truly appreciate the available power as well as the rounder and clearer tone at all volumes. The issue of cost; if my clients dont have the need for this level of quality why should they pay for a new board? Simply because it cost more to keep the board than to replace it. A beautifully rebuilt piano with a new pin block, new high quality strings, a completely restored action and a new finish, every thing but a new board, is a piano out of balance. Sooner or latter, before the other new parts need to be replaced, the soundboard problems will need to be fixed. Have you ever replaced a board in a piano recently rebuilt? I have, a number of times, and it is no picnic for the unlucky clients. Our discussion of this topic started with an inquiry about what kind of strings to use on a 1916 S&S O. Before you decide on the strings or the tuning pins and before you order the parts a decision has to be made whether or not it is worth doing all of these things without replacing the board. Thanks again for your interest. I could also send you a copy of Grand Piano Repair and Restoration Outline if you are interested. This is a hand out (describing various procedures and when in the life of the piano it is appropriate to use them) from a resent class I gave at the New York State Conference on evaluating pianos for restoration. I could send this directly or post it if there is interest. John Hartman
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